J3
The question
Why does my skin get darker where it's dry or irritated?
What's happening in your skin
On deeper skin, pigment cells are wired to respond to almost any irritation by producing melanin. Dryness is a low-grade irritation that never stops. Elbows, knees, knuckles, and eczema patches darken not because they're dirty or damaged but because they've been dry and rubbed for years. A smoke alarm set more sensitively goes off for toast.
What the research shows
The pigment response in skin of color is mediated by a signaling receptor that is increased in the epidermis of darker skin.
Rawlings, Int J Cosmet Sci 2006 (L019)Moderate
Lower ceramide levels in African American skin are consistent with the high prevalence of dryness.
Barrier properties study, 2010 (L018)Moderate · contested
Dryness-induced darkening is widely reported by consumers but is not well characterized in the literature.
Consumer basis: A014, A064
Our answer
Treat dryness as pigment prevention. Moisturize the spots that darken before they darken, and stop scrubbing them.
ActionCeramide cream on elbows and knees nightly for a month, then look.
Which product does this touch?HydroLipid Barrier Restore
Educational only, and not medical advice. Dr. Kita Skincare products are cosmetics. If a skin concern is persistent or painful, see a doctor.